Dr. Saad J. Saleh
Department of Electrical and Computer Engineering
Rice University, Houston, Texas
The development of autonomous vehicles has revolutionized geophysical and geochemical sensing. However, most of the current deployments employ such vehicles simply as individual platforms. Yet, many of the new emerging applications require deployment of a large fleet of unmanned vehicles moving collectively in a formation constrained to maintain a fixed geometric shape while maneuvering. This added complexity can be quite challenging for any geophysical data acquisition program, but it is particularly formidable for underwater platforms where GPS signals are unavailable and alternative localization strategies can be rather costly or inaccurate.
The advent of Formation Control Theory in recent years has provided a theoretical foundation for understanding and controlling formations and swarms through simple localized inter-vehicle exchange of information. In this talk, we present recent results from an analytical and numerical feasibility study to explore applicability of formation control theory to geophysical data acquisition. Specifically, we consider the problem of conducting a streamer-free mobile marine seismic survey. To this end, we examine a typical marine seismic survey layout, focus on the possibility of replacing the cable-linked receivers by sensor-carrying autonomous vehicles, and address the questions of inter-vehicle sensing and control algorithms required to robustly maintain the desired acquisition geometry while maneuvering. We present numerical simulation results to demonstrate the feasibility of this approach and to address the resulting tradeoff between cost and complexity on the one hand and robustness in the face of potential sensor failures on the other hand.